don't set and uid if not present on the object

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@12824 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/Document/BusinessTemplate.py

@@ -121,7 +121,8 @@ def _recursiveRemoveUid(obj):
   This is used to prevent unindexing real objects when we delete subobjects on
   a copy of this object.
   """
-  obj.uid = None
+  if hasattr(aq_base(obj), 'uid'):
+    obj.uid = None
   for subobj in obj.objectValues():
     _recursiveRemoveUid(subobj)